I am 21 years old and workout on a regular basis. I have been obsessing over the possibility of having a heart attack ever since my friend's dad passed away from one and my uncle had one and survived. I had an ECG done over a year ago and everything came back fine and I had comprehensive blood work and a physical done 3 months ago and everything was absolutely fine. Is there still a possibility that I could have an impending heart attack or is my chest discomfort/pain just muscular tension or stress. I know its rare for someone my age to have a heart attack, but I can't get the thought of it out of my head and I'm terrified to have one and die from it ever since I read that half of the people that have one die before reaching the hospital.

If you had a comprehensive workup done three months ago and everything was clear AND you're only 21 years old, you are in the best possible situation to not worry about a heart attack.

Anxiety about a heart condition can absolutely cause you to experience tightness in your chest. You know how if you have an injury you tend to tense up your muscles around it in an effort to protect it? Or if someone goes to tickle you somewhere the muscles get all tense around that area? This is a reflexive action that you don't even consciously do.

In this exact same way, when you have anxiety about your heart, you tend to tense up your chest muscles in anticipation of it needing protection. This tension ironically creates the very symptoms you dread which makes you think you are having a heart attack. You need to work on relaxing those muscles and not stressing out about your heart. You have no good reason to worry about it.